Scribe Notes on -
MPLS and Traffic Engineering
by

Soumya Sakha Tripathy
Y3111046
tripathy@





Comparison of Circuit Switching & Packet Switching :

Multi Protocol Label Switching :

**   Over View  :
**   MPLS Basics:
Here is a simple LSP :-

                                                                        LSP


   Here the packets are sent from the sourse router Ingress to the Destination router Egress. Each router in LSP adds the MPLS header to the packets and forwards it . Note that the forwarding to the next route in LSP is based on label not on IP Address.

**   MPLS Header :

 
 
                                 Label ( 20 bits )               
 CoS ( 3 )  S       TTL ( 8 bits)


       L2 Header
    MPLS Header
       L3 Header
                    L3 Data             

                                          
   L2 Header
    MPLS Header
     MPLS Header
   L3 Header
            L3 Data         

**   Fault Tolerance :


                                                                        Fig : fault tolerance





References :